Textbook treatments of the genetics of intelligence.

Abstract

Genetics textbooks have been remarkably unaffected by the discovery of fraud in the work of British psychologist Sir Cyril Burt or by the resulting critical review of other classic studies on the genetics of intelligence. Although Burt's name has nearly vanished from current textbooks, his results continue to be cited in textbook discussions of the heritability of intelligence, as do the results of other studies now recognized as methodologically inadequate. Moreover, genetics textbooks consistently employ confused or misleading definitions of the concept of heritability that, together with the reporting of discredited data, perpetuate a fundamentally inaccurate understanding of the genetics of intelligence. This situation is largely attributable to the practice--generic to textbook writing but in this case taken to an extreme--of authors' liberal borrowing from one another or from a few apparently authoritative works (including earlier textbooks). The extent to which authors rely on these sources for their discussions of the genetics of intelligence is apparently a function both of the controversiality of the subject and of authors' technical insecurity, perhaps reinforced by prior assumptions about the influence of genes on variations in intellectual performance.